ARM: dts: msm: Add MPP3 HDMI regulator for APQ8084

Remove the existing PMIC's MPP3 GPIO usage and use it as HDMI
voltage regulator to enable the power for HPD (Hot Plug Detect)
on APQ8084.

Change-Id: I55c3fb5cd11212baa0de3b44dd7eb3a260b2e7a5
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>